Xtykutl

In my app, the orientation is portrait by default, but in some special screens I want the viewcontroller to be auto rotated or to force the orientation to landscape.

in AppDelegate.swift :

class AppDelegate: UIResponder, UIApplicationDelegate {

var window: UIWindow?



// portrait by default

var interfaceOrientations:UIInterfaceOrientationMask = .portrait {

    didSet{

        // force to portrait

        if interfaceOrientations == .portrait {

            UIDevice.current.setValue(UIInterfaceOrientation.portrait.rawValue,

                                      forKey: "orientation")

        }

            // force to landscape

        else if !interfaceOrientations.contains(.portrait){

            UIDevice.current.setValue(UIInterfaceOrientation.landscapeRight.rawValue,

                                      forKey: "orientation")

        }

    }

}



func application(_ application: UIApplication, supportedInterfaceOrientationsFor window: UIWindow?) -> UIInterfaceOrientationMask {

    return interfaceOrientations

}

in only portrait vc:

override func viewWillAppear(_ animated: Bool) {

    super.viewWillAppear(animated)



    appDelegate.interfaceOrientations = .portrait

}



override func viewWillDisappear(_ animated: Bool) {

    super.viewWillDisappear(animated)



    appDelegate.interfaceOrientations = .portrait

}

in auto rotated vc:

override func viewWillAppear(_ animated: Bool) {

    super.viewWillAppear(animated)



    appDelegate.interfaceOrientations = .allButUpsideDown

}



override func viewWillDisappear(_ animated: Bool) {

    super.viewWillDisappear(animated)



    appDelegate.interfaceOrientations = .portrait

}

in only landscape vc:

override func viewWillAppear(_ animated: Bool) {

    super.viewWillAppear(animated)



    appDelegate.interfaceOrientations = [.landscapeLeft, .landscapeRight]

}



override func viewWillDisappear(_ animated: Bool) {

    super.viewWillDisappear(animated)



    appDelegate.interfaceOrientations = .portrait

}

but it still has bugs...Help me

You should force the rotation with:

UIDevice.current.setValue(UIInterfaceOrientation.landscapeLeft.rawValue, forKey: "orientation")

You also have to enable autoRotation

override var shouldAutorotate: Bool{

    return true

}

And of course, in your project settings you have to enable both portrait and landscapes modes.

You can custom your Portrait View Controller and Landscape View Controller. LandscapeViewController like this:

```

 override func viewDidAppear(_ animated: Bool) {

    super.viewDidAppear(animated)

    UIDevice.current.setValue(UIInterfaceOrientation.landscapeRight.rawValue, forKey: "orientation")

 }



 override var shouldAutorotate: Bool {

    return true

 }



 override var supportedInterfaceOrientations: UIInterfaceOrientationMask {

    return .landscapeRight

 }



 override var preferredInterfaceOrientationForPresentation: UIInterfaceOrientation {

    return .landscapeRight

 }

```

Some points need to notice: UIViewController can't decide to rotate automatically, you can use UINavigationController to fetch the value of rotation property:

override var shouldAutorotate: Bool {

    return (self.topViewController?.shouldAutorotate)!

}



override var supportedInterfaceOrientations: UIInterfaceOrientationMask {

    return (self.topViewController?.supportedInterfaceOrientations)!

}



override var preferredInterfaceOrientationForPresentation: UIInterfaceOrientation {

    return (self.topViewController?.preferredInterfaceOrientationForPresentation)!

}